26 research outputs found

    Hybrid Funnel Technique: A Novel Approach for Implant Site Preparation: A Pilot Study.

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    (1) Background: Different techniques and tools have been developed for implant site preparation. In this clinical scenario, Hybrid Funnel Technique (HFT), a novel osteotomy procedure, has been proposed. (2) Aim: The aim of this retrospective observational study was to consider the different responses to compression of the histological bony compartments (cancellus and cortical). HFT involves the use of multiple drills for the cortical layer preparation and of an osteotome for the osteocompaction of the cancellous bone. (3) Materials and Methods: Following computer-supported implant planning and guided surgery, 10 osteotomies with HFT were performed and 10 implants with the same length and diameter were placed in seven healthy and no daily smoking patients. Periapical X-ray and intraoral photographs were performed at baseline and after 12 months of follow-up to evaluate marginal bone level (MBL) changes and aesthetic results obtained from implant prosthetic rehabilitation. (4) Results: At 1 year of follow-up, 100% of the implants were successfully integrated, MBL change mean value was 0.17 mm ± 0.21. No differences in terms of MBL were noted between thin and thick biotypes. Pink esthetic score (PES) and white esthetic score (WES), assessed one year after definitive restoration placement, were 7.5 ± 2.3 and 8.5 ± 1.1, respectively. (5) Conclusions: Based on the findings of this preliminary clinical study, HFT has led to stability of peri-implant tissues and could represent a reliable technique for surgical preparation of the implant site

    COVID-19 outcomes in people living with HIV: Peering through the waves

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    Objective: To evaluate clinical characteristics and outcomes of COVID-19 patients infected with HIV, and to compare with a paired sample without HIV infection. Methods: This is a substudy of a Brazilian multicentric cohort that comprised two periods (2020 and 2021). Data was obtained through the retrospective review of medical records. Primary outcomes were admission to the intensive care unit, invasive mechanical ventilation, and death. Patients with HIV and controls were matched for age, sex, number of comorbidities, and hospital of origin using the technique of propensity score matching (up to 4:1). They were compared using the Chi-Square or Fisher's Exact tests for categorical variables and the Wilcoxon for numerical variables. Results: Throughout the study, 17,101 COVID-19 patients were hospitalized, and 130 (0.76%) of those were infected with HIV. The median age was 54 (IQR: 43.0;64.0) years in 2020 and 53 (IQR: 46.0;63.5) years in 2021, with a predominance of females in both periods. People Living with HIV (PLHIV) and their controls showed similar prevalence for admission to the ICU and invasive mechanical ventilation requirement in the two periods, with no significant differences. In 2020, in-hospital mortality was higher in the PLHIV compared to the controls (27.9% vs. 17.7%; p = 0.049), but there was no difference in mortality between groups in 2021 (25.0% vs. 25.1%; p > 0.999). Conclusions: Our results reiterate that PLHIV were at higher risk of COVID-19 mortality in the early stages of the pandemic, however, this finding did not sustain in 2021, when the mortality rate is similar to the control group

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

    Get PDF

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Osteoconductivity of bovine xenograft granules of different sizes in sinus lift: a histomorphometric study in rabbits

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    Devido à falta de dados sobre o contato osso-enxerto ao longo do tempo nas várias regiões dentro do espaço subantral do assoalho do seio maxilar elevado, o objetivo do presente estudo foi avaliar a osteocondutividade do osso mineral bovino desproteinizado (Deproteinized bovine bone mineral - DBBM) com grânulos de dois diferentes tamanhos aplicados para elevação do assoalho do seio maxilar. O aumento do seio maxilar foi realizado bilateralmente em 18 coelhos usando DBBM com dimensões de partícula de 0,125-1,0 mm ou 1-2 mm. A antrostomia foi coberta com uma barreira de colágeno. Os animais foram eutanasiados em grupos de 6 após 2, 4 e 8 semanas de reparo. MicroCT e análises histológicas foram realizadas. Após 2 semanas de reparo, o contato osso-enxerto foi de 10,9% e 11,9% para os sítios de grânulos pequenos e grandes, respectivamente. Após 8 semanas de reparo, o contato osso-enxerto aumentou para 65% e 62% nos locais de grânulos pequenos e grandes, respectivamente. Os maiores valores localizaram-se próximos às paredes ósseas e à janela óssea. O conteúdo de osso novo desenvolveu-se entre 2 e 8 semanas de 7,0% a 27,6% e de 6,1% a 27,6% nos sítios de grânulos pequenos e grandes, respectivamente. Resultados semelhantes em osteocondutividade e formação óssea foram encontrados em sítios de grânulos de DBBM pequenos e grandes.Due to the lack of data on bone-to-graft contact (BGC) over time in the various regions within the subantral space of the augmented sinus floor, the present study aimed to evaluate the osteoconductivity of deproteinized bovine bone mineral (DBBM) with granules of different sizes applied in maxillary sinus floor elevation. A maxillary sinus augmentation was performed bilaterally in 18 rabbits using DBBM with particle dimensions of either 0.125-1.0 mm or 1-2 mm. The antrostomy was covered using a collagen barrier. The animals were euthanized in groups of six after 2, 4, and 8 weeks of healing. MicroCT and histological analyses were performed. After 2 weeks of healing, BGC was 10.9% and 11.9% for the small and large granule sites, respectively. After 8 weeks of healing, the BGC increased to 65% and 62% at the small and large granule sites, respectively. The highest values were located close to the bony walls and the bony window. New bone content developed between 2 and 8 weeks from 7.0% to 27.6% and from 6.1% to 27.6% at the small and large granule sites, respectively. Similar outcomes in osteoconductivity and bone formation were found at both small and large DBBM granule sites

    Sinus Mucosal Damage Triggered by Synthetic or Xenogeneic Bone Substitutes: A Histological Analysis in Rabbits

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    Background: It has been shown in rabbit models that the sinus mucosa in contact with graft particles might experience a progressive thinning and perforations. The phenomenon depends on the graft used. Hence, the aim of the present study was to compare the damaging effects of a synthetic of a xenogeneic graft. Methods: Forty New Zealand rabbits received a bilateral sinus elevation. Both sinuses of twenty rabbits were grafted with a biphasic 60% hydroxyapatite and 40% β-tricalcium phosphate while the other twenty received a deproteinized bovine bone mineral graft. Thinned sites (<40 µm) and perforations on the mucosa in contact with graft particles were evaluated after 2 and 10 weeks (ten animals each period). The width of the pseudostratified epithelium was also measured as control. Results: After 2 weeks of healing, 61 thinned sites were detected in the Synthetic group and 49 in the Xenogeneic group. After 10 weeks, the number of thinned mucosae increased to 79 sites in the Synthetic group (p = 0.222 between periods), and to 114 sites in the Xenogeneic group (p = 0.030 between groups; p = 0.001 between periods). Perforations were few in the 2-week period, two in two sinuses out of 20 in the Synthetic group, and four in two sinuses out of 20 in the Xenogeneic group (p = 0.721). In the 10-week period, the perforations increased to eight in the Synthetic group, distributed in six sinuses out of 20, and to sixteen in the Xenogeneic group, distributed in 11 sinuses out of 20 (p = 0.082). The pseudostratified epithelium presented a reduced width at the thinned sites. Conclusions: The contact with synthetic or xenogeneic grafts will induce thinning and possible perforations of the sinus mucosa. This effect will increase over time, and it is stronger at the xenogeneic than the synthetic graft

    Clinical, Radiological, and Aesthetic Outcomes after Placement of a Bioactive-Surfaced Implant with Immediate or Delayed Loading in the Anterior Maxilla: 1-Year Retrospective Follow-Up Study

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    Background: Dental implants have become the standard for replacing missing teeth. However, patients’ demands for shorter treatment times and the desire for aesthetics in their results can complicate the rehabilitation process, particularly when poor-quality bone is involved. In order to address these challenges, new methods of treating implant surfaces have been introduced. These methods aim to make the implants superhydrophilic and bioactive, enhancing their functionality and interactions with the surrounding tissues. Aim: The aim of the study was to retrospectively examine the efficacy of a superhydrophilic and bioactive implant for treatment of the edentulous maxillary anterior area. The study also aimed to evaluate whether this improved implant surface, by enhancing the osseointegration processes, could serve as a factor in speeding up the loading protocols. Materials and Methods: For this retrospective study, a total of 13 implants were included: 6 delayed restored implants and 7 immediately loaded implants placed in the anterior maxillary area. Clinical, radiographic, and esthetic outcomes were assessed. Baseline measurements of the insertion torque value (ITV) and stability implant quotient (ISQ) were recorded for all implants. In the early-loaded group, these measurements were also taken 30 days (t30) and 45 days (t45) after the placement of the implant to monitor their changes over time. Marginal bone loss (MBL) was calculated according to the changes in marginal bone level on intraoral X-rays taken at two different time points: at baseline and one year after loading. To evaluate the esthetic results, the pink esthetic score (PES) and the white esthetic score (WES) were assessed. For this evaluation, intraoral photographs were taken one year after implant loading. Results: A total of 7 implants were immediately restored, with a mean ITV of 32.29 ± 9.01 Ncm and a mean ISQ of 72.71 ± 2.81. These implants were placed in a bone environment with a mean density of 410.00 ± 194.42 HU. On the other hand, 6 implants with delayed loading had a mean ITV of 28.50 ± 3.27 Ncm, an ISQ of 67.92 ± 8.43, and a mean bone density of 607.50 ± 140.83 HU. The mean PES and WES after 1 year were, respectively, 8.71 ± 1.89 and 8.57 ± 0.79 for immediate and 8.33 ± 1.36 and 9.17 ± 1.33 for delayed-loaded implants. At 12 months after loading, the immediately loaded group had a MBL of 0.29 ± 0.29 mm, while the delayed-loaded group had a MBL of 0.33 ± 0.25. No statistically significant differences between the two treatment groups were found for any of the evaluated outcomes. Conclusions: Despite the limitations of this study, the obtained results may support the use of a superhydrophilic and bioactive implant surface for implant-prosthetic rehabilitation in critical loading protocols with satisfactory esthetic results
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